The private pilot was taking off in a tundra tire-equipped airplane from a snow-covered off-airport site, on a Title 14, CFR Part 91 personal flight. He reported that during the takeoff roll the main wheels struck a snowdrift, and the airplane nosed over, resulting in substantial damage to the wings and wing lift struts. The pilot said there were no preaccident mechanical problems with the airplane, and noted in his report to the NTSB that he should not have landed at the off-airport site with a wheel-equipped airplane. The pilot reported that after the accident he manually activated the airplane’s 406 MHz Emergency Locator Transmitter (ELT), and within 20 minutes of doing so, he received a cell phone call from the airplane’s owner inquiring about the accident.